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451.
Hotspot detection plays a crucial role in grading of neuroendocrine tumours of the digestive system. Hotspots are often detected manually from Ki‐67‐stained images, a practice which is tedious, irreproducible and error prone. We report a new method to segment Ki‐67‐positive nuclei from Ki‐67‐stained slides of neuroendocrine tumours. The method combines minimal graph cuts along with the multistate difference of Gaussians to detect the individual cells from images of Ki‐67‐stained slides. It, then, automatically defines the composite function, which is used to determine hotspots in neuroendocrine tumour slide images. We combine modified particle swarm optimization with message passing clustering to mimic the thought process of the pathologist during hotspot detection in neuroendocrine tumour slide images. The proposed method was tested on 55 images of size 10 × 5 K and resulted in an accuracy of 94.60%. The developed methodology can also be part of the workflow for other diseases such as breast cancer and glioblastomas.  相似文献   
452.
Physicochemical Properties of Field Pea, Pinto and Navy Bean Starches   总被引:3,自引:0,他引:3  
Legume starches were compared for physicochemical properties that may explain differences in functional properties. Field pea starch had higher amylose, greater swelling power and solubility, and lower pasting temperatures than pinto and navy bean starches. Scanning electron microscopy (SEM) showed that field pea starch had larger, more irregularly shaped granules and more broken large granules than pinto or navy starches. The most starch damage was observed for field pea. Pinto and navy bean starches had greater resistance to swelling at 60°C than field pea indicating a more strongly bonded micellar network. Higher cold paste viscosity was observed for navy bean and field pea.  相似文献   
453.
燃煤电站汽水系统中低温给水部件由于流动加速腐蚀产生大量腐蚀产物,这些腐蚀产物随工质在整个汽水系统中迁徙,严重影响了机组的运行安全及寿命。基于质量平衡方程,建立了腐蚀产物的生成模型,从3种不同角度分析了金属氧化层孔隙率、铁在工质中的扩散系数和工质pH值等对腐蚀速率的影响。结果显示:腐蚀速率分别与前两者成正比关系,而与工质的pH值成反比关系。给水加氧处理可使金属氧化膜的孔隙率明显降低,而管道布置越复杂、管道表面越粗糙,铁在工质中的扩散系数越大。因此,燃煤电站在实际运行中,可通过管道结构优化,选择最佳给水处理方式,在最佳pH值和溶氧量条件下抑制流动加速腐蚀,减少腐蚀产物的产生。  相似文献   
454.
Hazelnuts (Corylus avellana L.) were collected from three different cultivars (Tombul, Palaz and Kal?nkara) at the harvest season of 1996. The dried nuts were stored shelled and unshelled in polyethylene bags at 21C and 60–65% relative humidity for 12 months. During storage, the total fat content increased, the palmitic and oleic acid content of the oil increased, linoleic acid, ranged from 12.41 to 10.35%. No significant differences were found for other fatty acids during storage. The effect of storage of shelled and unshelled hazelnuts on the total fat content was significant.  相似文献   
455.
A bovine longissimu; dorsi muscle was divided into anterior and posterior pieces, half of each piece was roasted at 140°C to 70°C. “Widths” or “diameters” of fibers from each position (anterior, posterior) and treatment (raw, cooked) were measured by three methods: A, width of separated fibers on a longitudinal plane; B, width of fibers in ongitudinal sections; and C, fiber diameter calculated from the area of fibers in cross sections. Bartlett's test for homogeneity of variance indicated greater (P<0.05) variance among observations by method A than by methods B or C; position-treatment variances were larger (P<0.05) for method A than for B or C.  相似文献   
456.
“Loring” and “Elberta” peaches and “Golden Delicious” apples were irradiated with UV (254nm) to doses of 0.84 × 104 to 40 × 104 erg/mm2 then stored. “Loring” were stored 10 days and “Elberta” 20 days at 12°C. “Golden Delicious” were stored 30 days at 20–25°C in a dark room. Fruit were examined and differences in percentage rot and in physical-chemical properties determined. Percentage rot decreased with increasing UV dose. Fruit were firmer, pH and soluble solids lower and acidity higher for UV-treated than for nontreated peaches; pH was lower and acidity and ascorbic acid higher in UV treated than in nontreated apples. Percentage weight loss was less for UV-treated apples. The results indicated that UV treatment not only reduced storage rots but also delayed ripening of peaches and apples.  相似文献   
457.
用铁尾矿陶粒替代普通混凝土天然粗骨料,根据《轻骨料混凝土技术规程》(JGJ/T 12—2019)设计配合比,制备LC30~LC40的铁尾矿陶粒混凝土。测定和计算其力学性能、耐久性、经济性,并与普通混凝土作对比。结果表明,铁尾矿陶粒混凝土能够满足《轻骨料混凝土技术规程》(JGJ/T 12—2019)中LC30配制强度,其强度与水胶比的相关性较普通混凝土弱,抗折强度和弹性模量分别仅有普通混凝土的60%和65%左右,但抗氯离子渗透能力和抗冻性能显著优于普通混凝土。本文研究了铁尾矿陶粒用于制备轻骨料混凝土的可行性和其混凝土的综合性能,为下一步装配式构件设计提供数据支撑,间接解决了陕南地区铁尾矿循环利用的问题。  相似文献   
458.
The purpose of this research was to determine and compare the physicochemical properties of probiotic frozen yoghurts made from camel and cow milks. The results showed that the viscosity of frozen yoghurt made from camel milk was significantly higher (P < 0.05) than that from cow milk. Less fat was destabilised in frozen yoghurt made from camel milk. The frozen yoghurt made from camel milk required more time for melting than that from cow milk. Flavour scores of the frozen yoghurt made from camel milk constituents were significantly lower (P < 0.05) than those made from cow milk.  相似文献   
459.
Paired wild‐type cultures consisting of a Lactobacillus paracasei subsp. paracasei (three strains) or Pediococcus pentosaceus (one strain) and a Pediococcus inopinatus (five strains) were used as adjunct cultures in the production of Iranian white brined cheese. After 8 weeks of ripening, adjunct‐treated cheeses produced by L. paracasei subsp. paracasei and P. inopinatus received significantly higher scores for flavour/taste, aroma, texture and overall preference than those produced by P. pentosaceus and P. inopinatus as well as the control cheese (P < 0.05). In conclusion, a greater improvement of sensory quality of cheeses was strongly associated with the presence of L. paracasei subsp. paracasei rather than pediococci.  相似文献   
460.
The objective of this paper was to investigate seasonal variations in bulk somatic cell totals and milk composition, evaluate the influence of somatic cell count (SCC) on milk fat and protein content and determine the effects of SCC on dairy farm profitability. A total of 1440 samples were analysed. Data were obtained by randomly collecting five samples of bulk tank milk from each of 24 dairy farms every month from April 2008 to March 2009. Milk was analysed for titratable protein, fat content and SCC (direct microscopic cell count). The highest total bulk SCCs were observed during autumn and winter. Conversely, higher levels of milk fat and protein were generated during spring and summer. A significant negative correlation was noted between SCC and milk composition, daily milk yield and milk returns. By logarithmic function, a significant negative relationship was observed between SCC and milk composition or milk returns. In conclusion, this study demonstrates that the SCC is a useful tool for judging dairy farm profit and milk quality.  相似文献   
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